Why Burma? Why Myanmar? Why Both? (npr.org)
"It's Burma and it's Myanmar. But which you choose to use involves some diplomatic considerations."
Why it's such a big deal that Obama said 'Myanmar' rather than Burma (washingtonpost.com)
"The United States still officially refers to it as Burma, even though the country's leadership renamed it Myanmar about 20 years ago. Neither name was an ideal option for Obama, who did use a number of phrases such as "this spectacular country." But you probably can't be the first sitting U.S. president to visit a country without using that country's name at least once, and he did: Myanmar."
As Myanmar Opens Up, A Look Back On A 1988 Uprising (npr.org)
"Until two years ago, Myanmar, also known as Burma, was ruled by the longest-running military dictatorship in the world. In 2010, the military began to loosen its grip on the country, increasing civil freedoms and offering some political and economic opportunity for citizens."